1. Field of the Invention
The present invention relates to an electrochemical gas sensor, and more particularly to a method for clamping the same.
2. Description of Related Art
The present inventors have developed electrochemical gas sensors in which the bottom of a gas sensor body is disposed in a metal container, a cover is disposed on the top surface of the gas sensor body, and the cover and the container are clamped via a gasket (Patent Document 1: JP 2004-226346A and Patent Document 2: JP 2006-84319A). Patent Document 1 discloses a configuration in which the tip end of the container is bent at a right angle from the axial direction of the container so as to press the gasket downward. Patent Document 2 discloses a configuration in which the gasket is in contact with the tip end of the container but is not provided near the gas sensor body. Patent Document 3 (U.S. Pat. No. 5,650,054) discloses a configuration in which a cover is received in the recess of a gasket.
Electrochemical gas sensors exhibit variation in their gas sensitivity, and those equipped with a water reservoir exhibit variation in the water evaporation amount as well. The variation in the gas sensitivity requires accurate adjustment of attached circuitry or reduces the yield of the gas sensor. Also, the variation in the water evaporation amount brings about variation in the service life of the gas sensor.
Patent Document 1: JP 2004-226346A
Patent Document 2: JP 2006-84319A
Patent Document 3: U.S. Pat. No. 5,650,054